According to Oliver, the Westland petrel was discovered in 1945 by pupils of the Barrytown school, Westland. The pupils wrote to Doctor Falla, director of the Canterbury Museum in Christchurch, in response to a radio broadcast about muttonbirds. They claimed that the local ‘muttonbirds’ laid their eggs in May, not in November, which led Falla to realise that these birds were different. After visiting the colony, Falla concluded it was a new subspecies of the black petrel. It was subsequently considered a separate species. However, both Maori and Pakeha had been harvesting the birds long before their “discovery”. The present day pupils of Barrytown School are still involved with the petrel’s conservation.

The Westland petrel is Red Listed by Birdlife International as a vulnerable species.

The Westland petrel breeds during winter in the foothills just south of Punakaiki in Paparoa National Park on the West Coast of the South Island. According to Birdlife International, in 1958, the population was estimated at 3,000-6,000 birds, in 1972, 6,000-10,000 birds, and in 1982, 1,000-5,000 pairs. In 1974, however, only 818 occupied burrows were located. Recent estimates put the total population at less than 20,000 birds, and c.2,000 pairs.

The Westland petrel are one of the few petrel species still breeding on the mainland. As they are among the largest burrowing petrels, they are less vulnerable to predation in the nest than smaller petrels. It nests in colonies on densely forested hills between 20-250 m. Burrows are usually concentrated in areas where the ground is relatively open, and where take-off areas are close by. Juveniles return to the colony as young as five years, but the minimum age of first breeding is 12. It migrates in summer to central Pacific and eastern New Zealand waters, and off South America.

It is a bycatch species of tuna longliners in New Zealand and Australia. Birds regularly follow commercial trawlers and may be killed when nets are hauled.

In breeding season, may be seen off the east coast from East cape to Banks Peninsula and off the west coast from Fiordland to Taranaki. Best place off the Kaikoura coast. Migrates to eastern Pacific, South American coast.

Credit for the photograph: —

Jan Hartog

Illustration description: —

Reference(s): —

Heather, B., & Robertson, H., Field Guide to the Birds of New Zealand, 2000.